In many countries, including the United States, the European Union and China, electronic signatures have the same legal effectiveness as traditional signatures or seals on paper.
Electronic seal simulates a traditional physical seal utilizing digital technologies. The management and usage of the electronic seal accord with those of the physical seal. Electronic files sealed with the electronic seal have the same appearance, validity and usage manner with paper files sealed with the physical seal.
The Electronic Signature Law requires that an electronic signature is valid in law only when it meets the following requirements:
(1) When the creation data of the electronic signature are used for electronic signature, it exclusively belongs to an electronic signatory;
(2) When the signature is entered, the creation data of the electronic signature is controlled only by the electronic signatory;
(3) After the signature is entered, any alteration to the electronic signature can be detected;
(4) After the signature is entered, any alteration to content or form of the electronic file can be detected.
In the European Union, the EU Electronic Signatures Directive was published in the EC Official Journal, as Directive 1999/93/EC of the European Parliament and of the Council of 13 Dec. 1999 on a Community framework for electronic signatures. In the United States, the definition of what qualifies as an electronic signature is wide and is set out in the Uniform Electronic Transactions Act (UETA) released by the National Conference of Commissioners on Uniform State Laws (NCCUSL) in 1999. From the laws of EU and US, it can be seen that if an electronic signature obtained by a technical scheme satisfies the Chinese digital signature law, it is also able to satisfy the EU Electronic Signatures Directive and Uniform Electronic Transactions Act.
In prior art, however, many hidden troubles exist in circulation of the electronic file. For example, the electronic file may be juggled during working process, the signature and seal of the electronic file may be fabricated. Thus, the requirements of the Electronic Signature Law are hard to be satisfied in the prior art, e.g., certain alterations to the content or form of the electronic file and the electronic signature after the electronic file is sealed with the electronic seal cannot be detected in the prior art.